An industrially advantageous synthetic method to obtain 2-substituted 5-benzothiazoleacetic acids (12), which have a strong antiinflammatory activity and low toxicity, was investigated. Consequently, 12 was easily obtained by only two steps using 4-chloro-3-nitrophenylacetic acid (8) as a starting material. After 8 was heated under reflux with sodium sulfide nonahydrate in water, bis-(2-amino-4-carboxymethylphenyl) disulfide (9) was obtained by acidification of the mixture with acetic acid. 9 was reacted with the corresponding aromatic aldehyde in pyridine in a mild condition to form 12 in a high yield. 12 and its esters were also synthesized by three other methods.

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Scopolia extract in the Japanese Pharmacopeia Ed. VIII, is prepared from the rhizomes of Scopolia spp. Pharmacological properties of scopolia extract was examined and following results were obtained. 1) In testing the permeation of alkaloids through the isolated small intestine of a mouse, it was found that the permeation rate of l-hyoscyamine in the scopolia extract was much slower than that of scopolamine present in the Datura root extract on that of pure alkaloid dissolved in the Tyrode solution. 2) The amount of l-hyoscyamine remaining in the intestinal lumen 40 min after application was similar in either case of scopolia extract or the pure alkaloid. 3) Application of l-hyoscyamine at a dose of 8 mg/10 g body weight killed all the mice within 11 min after oral administration, whereas a sample of l-hyoscyamine added with scopolia extract containing 8 mg of l-hyoscyamine per 10 g body weight, extended the lethal time and decreased the mortality. These results suggest that the pharmacologically unique properties of scopolia extract should be attributed to the decreased permeation of l-hyoscyamine through the intestine. In this sense the Datura root extract cannot be substituted for scopolia extract.

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With the expectation of analgesic activity, 3-substituted amino- or aminomethyl-2, 3-dihydrobenzofuran derivatives were synthesized, with special emphasis on the 5-position, corresponding to meta position of the phenethylamine skeleton. The intermediate 3-bromo-2, 2-dimethyl-5-methoxy-2, 3-dihydrobenzofuran had a high reactivity and showed various interesting characteristics. Cyanation of this bromo compound was difficult but 3-cyano-2, 2-dimethyl-5-methoxy-2, 3-dihydrobenzofuran was obtained in a good yield by the use of copper cyanide. This type of 3-cyano-2, 3-dihydrobenzofuran is a new compound. Analgesic effect of these benzofuran derivatives was equal to or less than that of aminopyrine.

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A new flavone glycoside, linariin, C₃₁H₃₆O₁₆, was isolated from the leaves of Linaria japonica MIQ. and Linaria vulgaris MILL. Linariin was assumed to be pectolinarigenin 7-(4''')monoacetylrhamno (1→6) glucoside on the basis of its mass and nuclear magnetic resonance data.

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In order to clarify the mode of degradation of ascorbyl monolaurate, kinetic study was made on its decomposition in aqueous solution under aerobic conditions. Thin-layer chromatography (TLC) of its degradation products indicated the presence of lauric acid, that results from hydrolytic cleavage of the ester bond, and other unidentified degradation products. The rate of degradation of ascerbyl monolaurate in aqueous solution was determined at 45°, 60°, and 80° in the pH range of 3.10-10.12 and at the ionic strength of 0.1. The pH-rate profile of the rate of disappearance of ascorbyl monolaurate from an aqueous solution and that of ascorbic acid was determined at 80°. The profiles showed that ascorbic acid is more susceptible to degradation than its monolaurate in the alkaline region. This phenomenon is probably due to either a micelle formation of the latter or a difference in the steric hindrance of molecular structure. The results of kinetic experiment or ascorbyl monolaurate in ethanol-water mixtures indicated that the logarithm of the rate constant varies linealy with the reciprocal of the dielectric constant.

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4-Oxo-5, 7-disubstituted-4, 5-dihydrofuro [2, 3-d] pyridazine was synthesized and reacted with a mixed acid. Substitution reaction of 2-nitro-4-oxo-7-chloro-4, 5-dihydrofuro [2, 3-d] pyridazine with sodium methoxide in methanol gave 2-methoxy-4-oxo-7-chloro-4, 5-dihydrofuro [2, 3-d] pyridazine and that with phosphoryl chloride gave 2-nitro-4, 7-dichlorofuro [2, 3-d] pyridazine and 2, 4, 7-trichlorofuro [2, 3-d] pyridazine.

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2-Phenylbenzothiazoline and 2-phenylbenzimidazoline were found to act as a hydrogen donor in purely organic systems, and are capable of reducing, a variety of hydrogen acceptors, such as Malachite Green, Shiff's base, quinoline N-oxide, azobenzene, chloranil, and benzil. The process does not require a catalyst.

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Aminolactam (XIII), dilactam (XVII), and thiadiazepine (XXI) derivatives were synthesized by the intramolecular ring closure of the aminoesters (XI, XVI, XIX), respectively. Reduction of the methiodide (XXII) of XIIIa gave the eleven-membered lactam (XXX) in a good yield, which, on treatment with lithium aluminum hydride, was converted to the corresponding diamine (XXXI).

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In continuation of a previous work resulting in the formation of pyrimidine N-oxide derivatives by the reaction of pyrimidine derivatives with hydroxylamine-O-sulfonic acid, the unusual reaction of hydroxyamine-O-sulfonic acid was attempted with quinazoline derivatives in the same way as in the reaction of pyrimidine. Quinazoline (I) gave N-(3, 4-dihydro-4-quinazolinyl) hydroxyamine-O-sulfonic acid (II), N-(o-cyanophenyl)-formamide (III), indazole (IV), and 4-aminoquinazoline (V). 4-Methylquinazoline (VI) gave only 4-methylquinazoline 3-oxide (VII), while 2-methylquinazoline (VIII) gave N-(2-methyl-3, 4-dihydro-4-quinazolinyl) hydroxyamine-O-sulfonic acid (IX), N-(o-cyanophenyl) acetamide (X), 2-methylbenzimidazole (XI), and 2-methyl-4-aminoquinazoline (XII).

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The reactivity of 3-position of pyrazolo-diazines to deacetylation or decarboxylation with conc. HCI and various electrophilic reagents was studied. The reactivety of these decreased in the order of pyrazolo-pyridazine and pyrazolo-pyrazine. By decarboxylation with conc. HCI or 40% H₂SO₄, 3-acetyl-2, 5-dimethylpyrazolo [1, 5-c] pyrimidine (XI) or methyl 5-substituted phenylpyrazolo [1, 5-c] pyrimizine-3-carboxylate (XII) were easily converted into 3, 4, 6-trimethyl-1H-pyrazolo [1, 5-c] pyridine (XXIV) or 5-substituted phenacylpyrazole-4-carboxylic acid (XXV), involving ring fission and recyclization.

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A colorimetric method for the determination of methanol with chromotropic acid was applied to the assay of the esterolytic activity of carboxypeptidase C_N (CPase C_N) with p-toluenesulfonyl-L-arginine methyl ester (TAME) as substrate. The method was found to be sensitive and useful for the determination of the esterolytic activity of CPase C_N. p-Nitrophenyl acetate, another substrate for esterase assay, was also used for comparison. The specific activity of CPase C_N was 0.60 unit/mg protein for TAME and 0.06 unit/mg protein for p-nitrophenyl acetate. The optimal pH and temperature for the esterolytic action of CPase C_N were pH 5.5 and 50°, respectively. Both carboxypeptidase and esterolytic activities were inhibited by diisopropylfluorophosphate (10^-3M) and HgCl₂ (10_-4 M). The activities were also decreased on reaction with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and glycine methyl ester. Preincubation of CPase C_N with TAME (50 or 100 mM) decreased the hydrolysis rate of Z-Glu -Phe by the enzyme.

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Fifty-one samples of Lycopodium plants (mostly Japanese species), including 17 species and 3 varieties, were collected and their triterpenoid constituents were examined firstly by comparing microchemically and then characterized by isolating them after alkaline hydrolysis. Discussions are made on thin-layer chromatography and chemotaxonomy of lycopodium triterpenoids, isolation and characterization of triterpenoids constituents, relationship between location of growth and the constituents, and relationship between species and the constituents. All the plants examined contained triterpenoids of serratane group or its assumed precursor, α-onocerin, the former including 13 new triterpenoids, 16-oxoserratenediol, 16-oxo-21-episerratenediol, 16-oxodiepiserratenediol, 16-oxoserratriol, 16-oxolycoclavanol, lycocryptol, 21-epilycocryptol, diepilycocryptol, lyclaninol, lyclanitin, 16-oxolyclanitin, lycernuic acid-A, and lycernuic acid-B, and two new glycosides of serratenediol and tohogenol. A new bisnortriterpenoid, clavatol, was isolated from L.clavatum. All these Lycopodium plants can be divided into three classes according to their major triterpenoids ; α-onocerin (L.clavatum, L.sitchense, L.obscurum, L.casuarinoides, L.inundatum), serratenediol (L.serratum, L.somae, L.cryptomerinum, L.chinense, L.sieboldii, L.fargesii, L.fordii, L.cernuum, L.phlegmaria), and 21-episerratriol (L.annotinum). Some of them (L.sitchense, L.annotinum, L.cernuum, and L.complanatum) showed variation in constituents depending on the locality of growth. Particularly, L.complanatum collected in Hokkaido contained α-onocerin as a major component, while the same plant from Taiwan did not contain α-onocerin but had 21-episerratriol as the major triterpenoid. Some plants of different species (cf. L.fargesii and L.fordii) were not distinguishable by their triterpenoid constituents suggesting their close relationship.

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Hydroxylation of 2-(2-amino-5-bromobenzoyl) pyridine (ABBP) to 3-OH-ABBP in animal liver was found to be mediated by the microsomal mixed-function oxidase system requiring nicotinamide adenine dinucleotide phosphate reduced form (NADPH) and O₂. When ABBP was incubated with microsomal fraction prepared from the liver of rats treated with phenobarbital or benzo [α] pyrene, hydroxylation of ABBP was enhanced about 2-fold of that of control rats. Hydroxylation of ABBP by microsomes of rats and rabbits was inhibited by SKF-525A, HgCl₂, CuCl₂, p-chloromercuribenzoate (PCMB), cytochrome c, and CO. The kinetic constants of ABBP hydroxylation by liver microsomes of various animal species indicated a similar affinity of ABBP. It is of interest that a factor which activates the hydroxylating activity was found in the soluble fraction of various organs of animals.

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Presence of 1, 5-anhydro-D-glucitol, a characteristic compound in Poligalaceae family, was found in Polygala senega var. latiforia in addition to arabinose, fructose, glucose, sucrose, melibiose, raffinose, and stachyose. Further, a new compound, 2-O-α-D-galactopyranosyl-1, 5-anhydro-D-glucitol, was identified, and 6-O-β-D-glucopyranosyl-1, 5-anhydro-D-glucitol was found for the first time in the natural product.

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In order to investigate the antibacterial activity of acylpentapeptides, the compounds containing the partial structure of lysine-colistin were synthesized by the acylation of pentapeptide obtained from tripeptide and dipeptide by dicyclohexylcarbodiimide reaction. Acid chlorides of 6-methyloctanoic acid (a component of colistin) and eleven other kinds of acid were employed as the acylating agent. It was proved that five acylpentapeptides have about one-half the antibacterial activity of colistin sulfate against gramnagative bacteria.

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In order to investigate the antibacterial activity of acylpentapeptides, the compounds, in which L-lysine in the side chain of acylpentapeptide reported previously was replaced with D-leucine of C-terminal and D-leucine of C-terminal with L-lysine of side chain, were synthesized by the acylation of pentapeptide obtained from N^ε-(formyl-D-leucyl)-L-lysyl-N^ε-formyl-L-lysine methyl ester (V) and N^ε-formyl-N^α-benzyloxycarbonyl-L-lysyl-L-threnine (VII) by dicyclohexylcarbodiimide (DCCD) reaction. The acid chlorides of three suturated fatty acids and two unsuturated fatty acids were employed as an acylating agent. The antibacterial activity of the synthesized acylpentapeptides was generally weak. It is, therefore, suggested that the acylpentapeptides should have the same amino acid sequence as that of the partial structure of lysine-colistin.

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Reaction of 4-cinnolinecarbonitrile (I) with ketones was attempted in benzene, in the presence of sodium amide. In the case of a methyl ketones acetophenone (IIa) and acetone (IIc), the -CN group in 4-position of I was substituted to give 2-(4-cinnolinyl)-acetophenone (IIIa) and 1-(4-cinnolinyl)-2-propanone (IIIc), respectively. In the case of an ethyl ketone, propiophenone (IIb), the reaction product was not isolated, but 4-ethylcinnoline (IV) was obtained when reacted with diethyl ketone (IId). IV was considered to be formed secondarily from 2-(3-cinnolinyl)-3-pentanone (IIId). Reaction of I with methyl ethyl ketone (IIe) afforded two kinds of a product, 1-(4-cinnolinyl)-2-butanone (IIIe) and IV. In this case, also, 3-(4-cinnolinyl)-2-butanone (III'e), thought to be the precursor of IV, was not isolated.

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The effect of additives on the stabilization, i.e., retardation of hydrolysis of aminoalkyl esters of phenylacetic acid [chemical formula] was examined. Among the esters I(R¹=H, R²=H), II(R¹=H, R²=CH₃), III(R¹=CH₃, R²=H), IV(R¹=n-C₃H₇, R²=H), V(R¹=n-C₄H₉, R²=H), VI(R¹=sec-C₄H₉, R²=H), VII(R¹=sec-C₄H₉, R²=CH₃), VIII(R¹=C₆H₅, R²=H), IX(R¹=m-CH₃O-C₆H₄, R²=H), the hydrolysis rate of VI was remarkably decreased by the presenced of nicotinamide, N-(hydroxyethyl) lactamide, and glutathione. The effect of these additives on the ester hydrolysis rate was studied in terms of complexation. The complex formation was examined by a kinetic procedure, solubility, partition, ultraviolet spectrum, and nuclear magnetic resonance spectrum. Among these, kinetic procedure and solubility method showed the formation of 1 : 1 complex.

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Silver [I] is quantitatively extracted by shaking with thiothenoyltrifluoroacetone (STTA) solution in xylene from an aqueous solution containing pyridine at pH 6.8±0.1. In order to eliminate the excess amount of STTA which reduces sensitivity of the existing method, ³⁾ the organic phase is washed with a basic washing solution (9 ml of pH 11.5 borax-NaOH buffer solution + 1 ml of pyridine) and silver is determined by measuring the absorbance at 360 nm against the reagent blank. This improved method has higher sensitivity (molar absorptivity, 12600) compared to the earlier method³⁾ (molar absorptivity, 5800), and the calibration curve follows Beer's law over the range of 3-30 μg of silver/10 ml of organic phase. The coefficient of variation in precision is 0.8% for 20 μg of silver. The molar ratio of silver [I] to STTA in extracted complex is estimated to be 1 to 1. Good results were obtained for recovery tests of silver on synthetic samples (copper + silver).

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Morpholino and trifluoromethyl derivatives of 2-phenoxyisobutyric acid were prepared and assayed for hypocholesteremic activities in rats. α-Morpholino-4-hydroxybutyrophenone (2), methyl 2-[4-(α-morpholinobutyryl) phenoxy] isobutyrate (4), and ethyl 2-(4-trifluoromethylphenoxy) isobutyrate (13) showed significant activities.

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Water-soluble derivatives of N-(2-chloroethyl)-N-nitrosourea were synthesized and their antitumor activity was tested against leukemia L-1210. Most of these compounds showed a high activity.

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Sulfated glyptide strongly inhibited gastric ulceration caused by pylorus-ligation with increasing dose, even though the anti-peptic activity was lessened at higher doses. Reduction of gastric acidity was observed with the increasing dose of sulfated glyptide. Sodium bicarbonate markedly reduced the gastric acidity but did not exert any appreciable influence on the development of gastric ulcer and peptic activity.

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